The present invention is directed generally to a device for alerting the driver of a rearwardly moving vehicle to the presence of any object in close range behind the vehicle. More particularly, the present invention is directed to a micro-wave radar device using the doppler shift principle to detect the presence of a moving target within the transceiver range.
The federal government presently requires that construction equipment such as tractors, trucks, graders, dozers, etc. have a loud audio alarm mounted thereon which constantly sounds when the equipment is being moved in a rearwardly fashion. The audio alarm is incorporated or connected to the reverse gear of the transmission so that the alarm will immediately sound when the vehicle is placed in reverse gear. A problem associated with the constantly sounding alarm is that operators of the equipment are experiencing hearing damage due to the fact that the alarm must be loud enough so as to overcome the background noise. A further problem associated with the present alarm is that the alarms are activated for such long periods of time that persons working in the vicinity of the construction equipment become immune or inattentive to the alarm.
It is therefore a principal object of the invention to provide an alarm device for construction equipment which is activated only when an object or person is behind the equipment and the equipment is about to be or is being moved rearwardly.
A further object of the invention is to provide an improved device for alerting the driver of a rearwardly moving vehicle to the presence of a person or object within a short range distance behind the vehicle as well as alerting the person or object who is within the short range distance behind the vehicle.
Finally, an object is to provide an alarm device for construction equipment which is economical of manufacture, simple and rugged in construction and efficient in operation.